Math help !!

[tokyoman]

Optometry school applicants decreased by 25% during a 4 year period. During the same time, the number of first- year opening in optometry school in creased by 12%. If the ratio of applicants to first year student openings had been 3 to 1, then which of the following would be the approximate ratio at the end of 4 year period.

A. 1.5 to 1
B. 2 to 1
C. 3 to 2
D. 4 to 3
E. 6 to 5

Ans : B

I got 2 to 3

lol which is not on the answer choices.

Can someone explain me please please please ??

---

Members don't see this ad.

 

[Dr NAT]

Applicants/1st year spots= (300-.25)/(100+.12) = 225/112 ~=2/1

 

[tokyoman]

Applicants/1st year spots= (300-.25)/(100+.12) = 225/112 ~=2/1

why 300 and 100? and why subtract?
can you elaborate a little bit more?

Im sorry, I am bad at math =( i can't fully understand

thanks in adavnce

 

[shiftypoptart]

its a ratio so it doesn't matter which numbers you use as long as its 3:1, you can even use 3 and 1. Basically whenever you have percentage if its an increase for example 12% you multiply the number by 1.12 which is faster than taking 12% then adding it to whatever number. When its a decrease for example 25% you would multiply by .75 which again is faster than getting 25% and subtracting it. In the end if you used 3 and 1 you would end up with a ratio of 2.25:1.12 which is equivalent to 2:1.

 

[tokyoman]

its a ratio so it doesn't matter which numbers you use as long as its 3:1, you can even use 3 and 1. Basically whenever you have percentage if its an increase for example 12% you multiply the number by 1.12 which is faster than taking 12% then adding it to whatever number. When its a decrease for example 25% you would multiply by .75 which again is faster than getting 25% and subtracting it. In the end if you used 3 and 1 you would end up with a ratio of 2.25:1.12 which is equivalent to 2:1.

Oh Yea.. It's crystal clear now =)

I got it =) Thanks so much